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Derivative Financial Instruments and Hedging Activities (Details) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 USD ($) Contract | Dec. 31, 2017 USD ($) Contract | Dec. 31, 2016 USD ($) | Jul. 01, 2018 USD ($) | Jul. 03, 2016 USD ($)
Derivative, Fair Value [Abstract] |  |  |  |  |
(Gains) losses in other non-operating income (deductions) | $ 1.5 | $ 6.2 | $ (0.8) |  |
Foreign Exchange Forward [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Number of contracts | Contract | 0 | 0 |  |  |
(Gains) losses in other non-operating income (deductions) | $ (0.7) | $ (1.2) |  |  |
Cash Flow Hedges [Member] | Interest Rate Swaps [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Notional amount |  |  |  | $ 150.0 |
Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Other Non-current Liabilities [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Fair value of derivative liability | 2.4 |  |  |  |
Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Other Assets and Deferred Charges [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Fair value of derivative assets | 2.7 |  |  |  |
Cash Flow Hedges [Member] | Cross Currency Rate Swap [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Notional amount |  |  |  | $ 150.0 |
Cash Flow Hedges [Member] | Cross Currency Rate Swap [Member] | Other Assets and Deferred Charges [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Fair value of derivative assets | 3.7 |  |  |  |
Cash Flow Hedges [Member] | Designated [Member] | Interest Rate Swaps [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Notional amount | $ 143.0 |  |  |  | $ 300.0

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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